SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f743cd275c07b0a40773b699222131867ded2bcf284a3f0884fc33a8066ab6fd' 
  AND token = 'cQV8z/ZEd/lM+DELqa8r/agyZXGBBChYxvOBdmiLqyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00095

JSON explain

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