SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2394fdceeb3a0219176661322af93ce086a5e427ad5584f0860c958ba121ee44' 
  AND token = 'vUB3gG4xHDuU7eWCC+Q3udmUNh88zCP2KGzKFZ/3PRM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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