SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f0c161fcc095c2caccac7a9096835e933f31d4a5346a4bc2c49395ab91fe76b' 
  AND token = 'hPboYhWhLl9oi1efncYSn0atpUeOaJnUKMJpb2yrwVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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