SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59f09964ef54b372b526054f4f9f0c011682e9fe606393a59de4810c905c4f45' 
  AND token = 'SL8YbBiPmAENtqVps+P1n4jkrIoVC3HdWq54zhWy38A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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