SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c17b882015c09cc07d958e72f74e8b0a011ca2faa0171a8497683b59da4644e4' 
  AND token = 'qeha+DBPhsrfKQQucbK2c66vt2uqoeBdAKCAnaXEJaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}