SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a5876d29ff9cd91a257c89c8a81376f165934e95a283a75dc46cc4c0e874102' 
  AND token = 'jzXZ9iUJUS00dZ44C5C3UnhHFyi+Era/e45tv/d2NOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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