SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dab7990b436d88f5ce223ff32e66198a6542b97690670ed5a25b32f46d37be93' 
  AND token = 'M4oTGNT3pH1vdH3Oc0qMvSb61q1mgFJRbcetGUKaMhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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