SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3479a0fc840a4ef3b57cd0bf8d61e9d15dcfe380527c5041e9d0b5a7ab708a9e' 
  AND token = 'm86aCEbSJ7kQpw4oufeva0Ts0izU8Q4F5kVJ4ZOa6WY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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