SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fa1bf173fa954a997cd5651467f3cad4030bba6bd688bcfb53466d7ad22a4a1' 
  AND token = 'Rpm1DG9bLSLlFEY4Bw32uqCoxV2K2nVruJgDjiFzGfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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