SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cc7208c48da73c452a0b1291b940fa0558a1f764233dbd86a6ea389096e54055' 
  AND token = 'ZS44W2Wudde+an6h7KydCYixwG/UkmVaN/qHjGAsDLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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