SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9d57f73b80a54c9a085b209034a8895180fc2587c195b2683cdfeb663857ad4' 
  AND token = 'AnntWhmYjuizt2eiRBpmR8DrHwG4IF92Du7HOm3S5K4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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