SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b9925c25275c4661272c68d00bb782e31fe65526986dea04b05aa6d62993512' 
  AND token = 'q8nFSpIJf4MBtbgrJDhs3IcuNEEwBVsZ1DcgLkQZ/rg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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