SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a46d96ba97797029057cd511b628fbc76cae1b7146434daa82f552bde0a0094' 
  AND token = 'fPq6eRcsJwKI7qjD+BYfNaIDQgQPRt4n3DodXA/G8Rg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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