SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96985c0cd4b52600c33e38cf4f4b792edfd7deddeeb496b3b30ab89b56ce5ce0' 
  AND token = 'xW1CzMSSVF2K95EQPh57VdoTZgKaw+rJgDuY3llXJPs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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