SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b0701c2a056e5007a0778b688d8444803ff6a3d9baf32261ba2b7572681a8f08' 
  AND token = 'abYUj0c12X5fC2ogGSoF+7GE0MY2u5C/roz67Xk549E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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