SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '734e06d4328937be6df5a8b2595e7ed044c0c924cacb6771420a871356131e82' 
  AND token = 'ib56jrYlifn42TrCJ80aG6bo/FgloDe9P1CE6ck80OA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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