SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a53f90df62629993bd8f0c7e559504ad2ba85b4b2811eaa3df16865e9f4b7e4b' 
  AND token = 'VVwYVV0Shx7g5ve9IffBzB5+njzoMqBqnBeGTvlH4vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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