SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb4dad27eecf8614fa32186ad5402fe65d798769ba16ab8efebe003543727098' 
  AND token = 'mkIYkAOpPob+TjqO3y2GnBXSURg+Dl+jOOS9NFLIPHo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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