SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9a4ae35734c33052d42d9670ea09339150e7dedd9ec85658c787e9bb1cec1a1' 
  AND token = 'ePf7XyeafINsdDBo3+51i6vDHDRgKojlmrlFnXmJfCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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