SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '20d2b4349aa1d2088cf68b398e1f3ca81c14a715faf273582b670b25891edb7e' 
  AND token = 'mL+lSITfVTfZzfi4N7+4jBC49qY3PH4d9pyaJLVHIUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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