SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '194efe5365c3a3cce04565e9b76a5671cd0c2c3201ee24cf99ec5a37672eb9c1' 
  AND token = 'vcqtKlY96Ct0KkzSqWPjxDsZ1BQKSYqU4WN8+R9nVIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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