SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41bf54100c6fd4481b7fc089d2302cc24433a30d79b5841d44d672c5eac20737' 
  AND token = 'nZ/YZmxuA65XKYDDEIkctjCneZjbCDhK4N4QYh0tbHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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