SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'becfb840ae977f27d9f0f9968d2b59149f2d15458bcdcf354005a10305ff75ae' 
  AND token = 'ZK6AK5XBwxDNPWm2+ZDe9tmrHVshh6Y/oSlaCesHjsQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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