SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ead9ea4ce035c9bccec568c740f439081bf9050c47be3a35c72d2b0ffe6c4e14' 
  AND token = 'zrRgv2zejxNeSOrn9A+pWYKskkEBP6f/YaD79pj1XhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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