SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4fffc10a5df2105a4e72b67282b627c55dc179118e4b7a000cf37b26b4183c6' 
  AND token = 'CwWOqRHP/G2a2FmV8itLfYx6zPKFwPEWiALdV8E205A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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