SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a12c9105baace76930de2f6fdbd962be13d33da27626dafedcd89a750bec06a' 
  AND token = 'U5agTHhGsTrRs7OrQWarzMFLS9l1Fe6NjqlKyNXRR2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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