SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11f69eaade6546fe1c7355ae29c3d75f6410cc87df5b93700c735bd63f3c5d55' 
  AND token = 'EL44bTCgPw2JLMLWuOf7JICKJzzoi8NZbzRep3+XfQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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