SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d80ec05a109f8d4af758b85fdef316a1b817c5f607988b9645d1b064d2b7def' 
  AND token = 'EoazjQoustfeAKs5b/9zQX+wzKA/HA1kUECsjyjSI08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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