SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a5190fec80e93c271bd089bd5e2a6c18c2257258a3eab57ef69f99289eca2d1' 
  AND token = 'ZPA8neSRNs4D9k/tqDqBpNVNsdZ8i85ik6CcmPDiHuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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