SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '267f57753c24591fbaf6c830137ee51834e6a5fb583211d768c767185e82e11a' 
  AND token = 'DBwAQnLyMRDGjqdxmLvgw3Rm/BucHnLHyY06z/kK3Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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