SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '094d9bca6f5c94d6b9283de9750d51e0e04e4afa090aa1d5efea67037472292b' 
  AND token = 'xrV+93sJ+MTyqVT5UyYdN5XJdGizMGW/+P+Ju0wT51I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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