SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4b20827307a1ce45fdc4e29a3975640d89ce9e3c4000b65e346f805a36e5f16b' 
  AND token = 'ArVFPqO5z15LLf6cUnMFR5kQjR+oLNQ3QOVLdn7eLJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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