SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ace8e117bb6495331cfbb4225bda195e9268af70b424467605e66a8b16b43961' 
  AND token = 'CyqmJrB9sEmPBXXtOmIA3p3vJ5MKsdgJV4npZmwCOBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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