SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '132db16e01a969f48fa0e0bbc0305ba07689fdb47733d8a40483c11055260098' 
  AND token = 'PHJUf0+1UNo5Gx6EaavR7fTEgXS2AL0qhZ0dSSR/Y3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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