SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eea707ea05ca82ec2e60ed3725682c00875fc1eadf04844f512a09318fc2cd56' 
  AND token = 'C8U0b6MBOyKzTZPlWqyV+BQLH+KAagyKrDFQhfdU7SA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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