SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c9b198c5c60b1543749d65a9a8994a09629c4555f3facbc7f114d77270f2b938' 
  AND token = 'S0UVqjM0BpH+pVMI9N1fZLu5I+/79XjxOuwubax9DYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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