SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '587b7051435877e83e1829f07086a0fc433f6cdcc1392e0e0b87552af1bf9218' 
  AND token = 'VTeV/V/urLs02v5DOrFwZOadPcfr4U97K6FDlZYR1RE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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