SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed0800496ae9aa757dd23ca3070cab236b1416478a660a12346abc765c6d8167' 
  AND token = 'FhYcXTHA5FvKon39cNzhmJYvPUM4/F42E+R8+taM1Qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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