SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'be5a1fdad2c6d5cf9fda224acd71bee728793404da079fd80b43a20347ace8fd' 
  AND token = 'zdQvyakWXTsBKddJkkIw+uB1+3RVGfGymJGJeI4JxAE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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