SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b112ba975c6cb30e56bc56d99105063c43f643c781c566326ff02bd804769287' 
  AND token = 'cDmFwXKM/02FOXfjWTLy2IoMJIwSHPCM985CS+4jVPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}