SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fa9ba0c550b4312d85931269112091d49bd4b62d80b712d25a0dd417bed8f25' 
  AND token = 'AFcfPQuKVSk5lPCsyTU6RStpvrI/aGVLPdubi2hgvCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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