SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db706ec544fc49c5ede37167d3f24c036313f52ad5b97671e52b7e485f8651e6' 
  AND token = 'aQDWmZfJ6iXwtSqoHMS3JWSdQJcl5nufBR0zx8qGftQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}