SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df991f4085d84bc1ecff9d0243ffe7e628a3876eb41afd8aa4278e57220e6082' 
  AND token = 'sqt19HCc481tjrie308NRSjvJO5R11DAQVbGf/Ec0oY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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