SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3bb8290d069ea605c597d8c106cc75c005447dfc1eeb454126455c48a1242188' 
  AND token = '2CJCwaGooExW1vPWGnvkN3xULMIN9e29EKbrk/80J7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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