SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '709269a856d53983fce1d26c047ab786bcc86620ad24bd3c32bc37484137e86f' 
  AND token = 'G4HOzCZiwrOMcXtIHDgRQ9XX20HUnHIpCBRVHMPwMaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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