SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0089337ad1e6844e9a2728e8767335d3868437756bd79c5e24150d53b7f02dfa' 
  AND token = 'fQpMagjqbyN5J7OZtBCI3QcxlfgDJldtlalvM/AJRO4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00076

JSON explain

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